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Corrosion behaviour of AZ91DSm1.0 with different preparation methods(vacuum melting and common melting) is investigated. X-ray diffraction(XRD), optical microscopy(OM), scanning electron microscopy(SEM), energy dispersive spectroscopy(EDS), corrosion weightless experiment and the potentiodynamic polarization curve are applied to characterize the corrosion behaviour. Results show that vacuum melting alloy possess higher corrosion resistance than common melting alloy. This is attributed to the rod-shaped Al3Sm which was formed in common melting alloy will have certain fragmentation effect on matrix that can lead to defects.

Instrument analysis method is used in this experiment, which detecting the zirconium content of zirconium powder by using plasma-atomic emission spectrometer. In this experiment, the instrumental detective conditions were determined, and analyzed several main factors affecting the experimental results, concluded the effects of temperature, hydrofluoric acid and deionized water on dissolving zirconium powder, summarized the method to detect zirconium powder content directly by ICP.

An investigation was carried out into temperature distribution in 3KA rare earth electrolytic cell and changes of products quality in neodymium electrolysis from a factory in China, The results show that the different temperature distributions have direct effects on the neodymium products quality. In same production cycle, the cell voltage of electrolytic cell is stable and curre rocessing before discharging bascially stays the same; In different cycles, temperature distribution not always alike, mainly reflected in lateral distribution of temperature in electrolytic cell, one form is temperature gradually increased from cathode to anode, and the anode temperature is highest; another is temperature declined then elevated again, anode temperature is slightly higher than the temperature of cathode. The second distribution is benefit for improve the quality of products.

The improved maximum power point tracking (MPPT) control based on the reduction of tracking range could reduce the tracking distance of wind turbine effectively, and improve the tracking efficiency. In this study, the relationship between the compensation coefficient of the improved MPPT control and several factors was investigated. Based on simulations of the simplified wind turbine model, wind conditions, air density and wind turbine parameters were used in the studies to investigate the relationship between the optimum compensation coefficients and these corresponding conditions. It can be indicated that in the fact, compensation coefficient is majorly determined by the tracking targets of MPPT and the dynamic performance of wind turbines that determined by the conditions mentioned above. The results also provide guidance for further studies in this area.

Concentration distribution of Nd2O3 in 3KA rare earth cell was studied by a self-restraint sample instrumentation of high temperature molten salts. The results were shown that concentration of Nd2O3 in this system was less than 4%, and the concentration of Nd2O3 decreased from top to bottom on the portrait, but it would be increased a little bit in the bottom point, and the concentration of Nd2O3 would be gradually increasing from cathode to anode.

The effect of negative pulse voltage on the microstructure and corrosion resistance of microarc oxidation film of A356 aluminum alloy treated by microarc technique was investigated by SEM, coating thickness gauge and electrochemical workstation etc. The results show the negative pulse voltage greatly influences the microstructure and corrosion resistance of microarc oxidation film by its electrode reaction. The film thickness increases while the size of pore and roughness of the film surface decreases initially and then increases with negative pulse voltage increasing. The microarc oxidation treatment considerably improved corrosion resistance, and the highest corrosion potential was -1.16V, which was 0.38V higher than that of substrate, and the corrosion current was lower than that of substrate about three orders of magnitude.